Patent GB-730674-A (GB)
Title: Improvements in and relating to the manufacture of products of concrete
IPC: B28B23/06
Filed: 1952-12-04
Abstract: 730,674. Moulding reinforced concrete pipes &c. HEIDENSTAM, E. J. VON. Dec. 4, 1952 [Dec. 5, 1951], No. 30765/52. Class 87 (2). Reinforcements 19, particularly reinforcing wires, are stressed between two end holders, 21, 22 and are embedded in concrete, the concrete being shaped by means of a mould 9 that slides or rolls vertically upward along the stressed reinforcement, the concrete being filled into the mould during displacement of the mould along the reinforcement. Shortly before the mould reaches the upper reinforcement holder 22, viz. at position 33b, the moulding operation is stopped, the mould is raised towards holder 22 until it is clear of the concrete and occupies position 9a, and a new reinforcement holder 39 is secured to the reinforcement, this holder being supported by beam 38. The reinforcement is then cut above holder 39, the mould is raised, carrying with it beam 23 which initially supported holder 22, to a position above the upper edge of walls 40, and the mould may then be transported to a position above another shaft. The concrete products are later lifted out by attaching the upper ends of the reinforcements to a beam and raising the beam (Figs. 5 and 6, not shown). The drawings show plant comprising six vertical shafts 1 in each of which eight pipes or poles are cast by means of moulds 9. Through each mould extends the vertical reinforcement and horizontal reinforcement (not shown). A string of products may be made by using mould partition plates slotted to accommodate the reinforcement. The beams 23 rest on the walls 2 of the shaft. The reinforcement is supplied from reels 24. In pits 26, 28 at the bottom of the shafts is a supply of sand, clinker or other material 26, which may be filled into the shafts as casting proceeds, to support the freshly-cast concrete: in the case of pipes the sand &c., may also be filled thereinto. The moulds 9 are carried by a beam system 10 which can be raised or lowered by means of cables 11 attached to a drum 12 mounted on a carriage 13 running on rails 15 which encircle a central lift shaft 5. Shaft 5 provides for the transportation of material (concrete, sand) and has lifting mechanism 7 for a bucket 8, and balconies 6. Concrete is fed from hoppers to a mixer and thence down a shoot to the lift shaft 5. In operation, the moulds are filled with concrete and raised, and sand 25 is filled into the shaft until the moulded product reaches the position 33b; in each shaft the work is done by a man on a central platform 35 connected with the moulds, and as the platform rises a slot 45 in the wall of the shaft is closed by a jalousie (to keep the sand in: if sand or other filler is not used, the jalousie may be omitted). The longitudinal reinforcement of the product may be fitted with clamps to enable the product to be lifted (Figs. 5 and 6, not shown). A wheeled carriage having a lifting beam may run on the shaft walls (Fig. 7, not shown). In modified arrangements of plant, (a) (Figs. 8 and 9, not shown), eight shafts 1 may be arranged in two groups of four, facing each other, and (b) (Fig. 10, not shown) the shafts 1 are replaced by an annular space surrounding the lift shaft.